Mobile re-education facility?

Mobile Cinema, newly reconditioned and fresh off the lot in 1967, via BLDGBLOG

This mobile cinema – essentially a big home theatre setup in a bus – just shouts “Doctor Who” to me.  Especially that second, older image with the extra signage “Ministry of Technology” and “Operated by PERA”, and the black-suited men being lead into the van by the white-lab-coated operator (and notice the second operator in the glass dome at the front).

Alternatively, there’s something about it that also resonates with Lovecraft’s Nyarlathotep, the image of Nyarlathotep as a kind of travelling showman whose shows are more than they might appear.